Root-induced changes in nutrient cycling in forests depend on exudation rates
نویسندگان
چکیده
(1) While it is well-known that trees release carbon (C) to soils as root exudates, the factors that control the magnitude and biogeochemical impacts of this flux are poorly understood. (2) We quantified root exudation and microbially-mediated nutrient fluxes in the rhizosphere for four ~80 year-old tree species in a deciduous hardwood forest, Indiana, USA. We hypothesized that trees that exuded the most carbon (C) would induce the strongest rhizosphere effects (i.e., the relative difference in nutrient fluxes between rhizosphere and bulk soil). Further, we hypothesized that tree species that associate with ectomycorrhizal (ECM) fungi would exude more C than tree species that associate with arbuscular mycorrhizal (AM) fungi, resulting in a greater enhancement of nutrient cycling in ECM
منابع مشابه
Plant responses to stress impacts: the C we do not see.
The flux of soluble organic carbon (C) from roots to soil (hereafter ‘root exudation’) is believed to have profound effects on C and nutrient cycling in ecosystems. Root exudates can comprise up to 10% of net primary productivity (NPP) in forests (Grayston et al. 1997, Phillips et al. 2011) and may accelerate C and nutrient cycling by up to 30% (Brzostek et al. 2013, Yin et al. 2014, Finzi et a...
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